So here's the story of my search for perfect portable headphones (that are not earbuds, I can't stand them, nor noise-cancelling and thier stupid batteries) and my review of the Pioneers:

I picked up the Pioneer SE-MJ31's at the airport in Guangzhou China. Now I have allot of headphones I guess: Beyer DT770's 32ohm (custom), Beyer DT770 Pro 80ohm, Bose "around ear headphones" (garbage), Sony MDR V600 (basically garbage too), Sony MDR V700dj. My first headphones were some crap that came with a sony cassete walkman in the 80's. After that were Sony MDR V50 or something like that.

I bought the DT770's 32ohms for portable use after my Bose fell apart after a year (the "pleather" ripped out of the earcups and also cracked apart). The Bose were ok, not the best, but turned out to be utter crap in the end. I had my DT770 Pro 80ohms for a long time so I knew they were good but I didn't want to run a portable amp with my Nokia 5310 music phone I use, to use them. Plus for portable use they are just to big around my neck when I'm not listening.

I figured I could live with it and ordered the DT770 32ohm anyway, but found that no, I can't deal with headphones that big and a cord that long.

Then I bought the Sony MDR V700's on a trip to Hong Kong, at one of the Sony stores in a mall there. I found that these were sort of annoying for portable use as well. The plug end was made long so you could hang the headphones on them while DJing. I used to DJ a bit long ago, but I wouldn't ever be needing that now, so it was just a pain as it made it harder to fit in your pocket when connected to your player. As well even they folded, they were a bit annoying around the neck. Also, the earcups were not deep, they would tend to slip off my head if I just so much as looked up at anytime. The coiled cord too...agghhh....annoying.The sound is ok, I like Electronic: hip hop (Kool Keith mainly), techno, hard house, acid house, and a bunch of other stuff, whatever it is, I don't care. I'll listen to whatever, all kinds of wierd stuff, I don't care what people think, but it's mainly electronic. For all of this stuff, they sounded decent on my phone.

So I just couldn't deal with the Sony V700's either for portable use. I found myself wearing them out less and less.

I actually went back to my OLD Sony MDR V600's. I hadn't used them in years, and wow they sounded like crap. But they were light, the plug was ok; it fit in my pocket better than the MDR V700's, and they still *flipped out of the way around my neck. But the sound was crap. No mid, all high and low, I just couldn't deal with them. Plus the ear pads were coming apart... and they were big around my neck as well... really long coiled cord too... I was about to give up.

So I'm walking through the airport with these annoying MDR V600's around my neck and the million foot long cord bunched into my pocket when I spot a little electronics shop with some headphones on the wall. I have time before my flight so I go in and spot the Pioneer SE-MJ31's.

I check the specs... wow 32ohms... 8-30 000hz (I think it said that)... I listen to them on my phone... the sound is like mini DT770's!! what!!?? They are "on ear" but they nearly cover my ears actually... pretty comfortable... very small, AND they fold, they are "dj style"...they are feather light... really short cord... small jack... I am SO getting these!.

I got them for 600RMB (about $90usd). Worth every penny. I wear them everywhere. Perfect portable headphones. Fit around my neck nice, I don't even know they are there. Nice and light on my head and never slip off. Everything is perfect about them. The sound is amazing considering the size. Heavy bass and treble, good mid... sound is so nice.

I recommend these to anyone that wants a headphone you can wear all day, while walking around, and have great sound. If I would have found these to start with damn, I would have saved some money. I guess they did just come out with them though.

So that's that. Not a real technical review but an honest one. And NO, I don't work for Pioneer.

I got them for 600RMB (about $90usd). Worth every penny. I wear them everywhere. Perfect portable headphones. Fit around my neck nice, I don't even know they are there. Nice and light on my head and never slip off. Everything is perfect about them. The sound is amazing considering the size. Heavy bass and treble, good mid... sound is so nice.

I'm sorry to tell you this but you kind of got ripped off. I got the same headphone in Japan for around 3000 Yen which is around $30-35 in the US. Still great headphones though.